Tuesday, 22 January 2013

It is my long held intention to become a licensed radio amateur, but with limited spare time over the last few years I simply haven't got around to it. I have the necessary technical knowledge but don't have the practical experience. I have dabbled with PMR-446 transceivers but they don't allow many 'legal' experimental opportunities.

So when my family asked me what I wanted for Christmas I said "You can buy me a CB Radio" and they did!

It is a Midland 78 Plus Multi it has the legal 40UK/40EU channels, plus it can be set to European and North American frequency bands.

It isn't the first CB Radio I've used, back in the early 80s when I was at school I managed to blag the use of the a friends set up with a small magmount antenna on a biscuit tin joined in the new craze! My handle was Morroco Mole ;-)

I am experimenting with the set up at the moment, powering it from a modified PC supply which is giving out a nice stable output a little over 12V. I have constructed an inverted-vee antenna out of some spare cable. It is currently in the middle of the back lawn, the central mast is only around four meters high and the elements are set approximately 45 degrees to the vertical. It has an 'ugly' air choke and using a £10 SWR meter I've tuned it and the worst ratio I get is a little over 1:1.5.

It all seems to work but at the moment I don't seem to have anyone to talk to on either the UK or the EU/CEPT channels. I've heard the odd transmission on some channels but they have been from nearby Mansfield and Nottingham.

I have monitored CB frequencies before with my scanner with limited success and was hoping for better with a proper CB radio. It is still early days but I think I may need to rethink my antenna until I get around to getting my mast sorted. I might have to stick the inverted-vee in the loft.

I was tinkering on Sunday afternoon and I switched the radio over to AM just as some more "Superbowl" skip came in, they really are amazing to listen to!

Tuesday, 8 January 2013

This was a nice opportunity to listen in since the position of the
ground station at the school meant the UK could listen in to the
majority (if not all) of the downlink. Usually when it is further east
in Europe (Germany/Poland etc) you get the initial calling and the start
of the contact but the ISS goes out of range before the session ends.

So I set up my FUNCube Dongle PRO PLUS connected to the discone in the loft and the new SDR-Radio V2 Preview software. I had to start the recording remotely as I was in work, but have played back the IQ file and made a video showing the decoding.

As you can see/hear I appear to get the full contact and the questions were (source)

1. What is the temperature outside the ISS?
2. What does the Earth look like from the ISS?
3. What does the Moon look like from the ISS?
4. Have you already passed through an asteroid belt?
5. Are you able to go outside the station, into the space?
6. What is your speed? Can you feel it?
7. How do you sleep? Do you have the same sleep pattern than on the earth?
8. Do the crew members sleep one after the other, or do you sleep all at the same time?
9. How do you know if it is morning or night on board?
10.Do you do any sports and physical activities? Do you lose weight?
11. Do you shave every day? If so, how?
12. Do you see any space debris? Can you see evidence of pollution of the earth?
13. What are your hobbies on the ISS after a day of work?
14. Are you happy to come back home at the end of your mission?
15. What is your current mission?
16. Why did you choose to become an astronaut?
17. How do you cook food? What is a typical meal in the ISS?

I was lucky to receive it given the interference monster was back! It does manage to get in on the act a few times but thankfully doesn't stop the show completely.

Over the last few months I've been suffering from increasing interference on the VHF/UHF and HF bands. Some of which I know about, the router I have puts out quite a few spikes on VHF but something local to me is putting out huge amounts of QRM.

I know it isn't internally generated as it disappears when I remove the antenna. I have gone around and powered off all the potential culprits in the house and discovered a switch-mode power supply for an external USB hard drive was throwing out some HF noise as was a digital photo frame.

I've suffered with interference on and off since getting back into the hobby back in 2010 and appreciate it is something I have to live with but it is quite annoying at times. I suspect the interference might be one of those power-line networking devices, but if anyone has any idea I would welcome a comment!

Wednesday, 2 January 2013

Tonight and tomorrow see the Quadrantid Meteor Shower (article on Telegraph website) Nasa scientists are predicting the morning skies are this week set to be filled with hundreds of shooting stars in the year’s first meteor shower.

Recently I have been reading up on amateur Radio Astronomy, one easy project is the detection of meteors using radio scattering.

On the British Astronomical Association, Radio Astronomy Group website there is an interesting project (a PDF download) which demonstrates how to use a FUNCube Dongle to detect reflection of the Graves Space Surveillance Radar signal from ionisation trails.

The Graves French space surveillance transmitter located
near Dijon, operating on a frequency of 143.050MHz the FCD was capable of
receiving the weak backscatter echoes from meteors, indeed I experimented last year and with a simple antenna picked up many squeaks and whistles from the normal 'background' meteor activity.

So I've set up my equipment again and will be doing some recording overnight.in the hope of a barrage of strange noises!